<!DOCTYPE html>
<html lang="en">
	<head>
		<meta charset="UTF-8">
		<title>zuoye2</title>
	</head>
	<style>
	    * {
	    	margin:0;
	    	padding:0;
	    }
		

		.box {
			width: 500px;
			background: #ccc;
			overflow: hidden;
			padding: 15px 10px;
			margin: 50px auto 0;
		}

		.left {
			width: 300px;
			height: 17px;
			background: #369;
			float: left;
		}

		.right {
			width: 200px;
			height: 17px;
			background: #f90;
			float: right;
		}

		.left, .right {
			margin-bottom: 10px;
		}

		.a {
			margin-bottom: 0;
		}


	</style>
	<body>
		<div class="box">
			<div class="left"></div>
			<div class="right"></div>
			<div class="left"></div>
			<div class="right"></div>
			<div class="left"></div>
			<div class="right"></div>
			<div class="left"></div>
			<div class="right"></div>
			<div class="left"></div>
			<div class="right"></div>
			<div class="left a"></div>
			<div class="right a"></div>
		</div>
		
	</body>
</html>